minushalf band-gap¶
$ minushalf band-gap --help
Usage: minushalf band-gap [OPTIONS]
Uses output files from softwares that perform ab initio calculations to
provide the locations of VBM, CBM and the Gap value in electronvolts.The
names of the files required for each software are listed below, it is
worth mentioning that their names cannot be modified.
VASP: PROCAR, EIGENVAL, vasprun.xml
Options:
-s, --software [VASP] Specifies the software used to perform ab initio calculations.
[default: VASP]
-b, --base-path PATH Path to folder where the relevant files are located.
--help Show this message and exit.
Examples¶
To demonstrate the command usage, one calculated the positions of CBM, VBM and the Gap value of SiC-2d .
VASP¶
The following input files were used:
SiC POSCAR
1.0
3.100032 -0.000007 0.000001
-1.550022 2.684696 -0.000002
0.000006 -0.000010 20.000000
Si C
1 1
Selective dynamics
direct
0.666667 0.333335 0.295447 T T F
0.000000 0.999998 0.295392 F T F
PREC = Normal
EDIFF = 0.0001
ENCUT = 500.0
ISMEAR= -5
ISTART = 0
LREAL = .FALSE.
LORBIT=11
Kpoints
0
Gamma
12 12 1
0.0 0.0 0.0
Electronic properties are investigated within the DFT by applying the Perdew-Burke-Ernzerhof (PBE) functional within the general
gradient approximation (GGA) [2]. After running the VASP program, the minushalf band-gap command returned the following output:
$ minushalf band-gap -s VASP
_ _ _ __
_ __ ___ (_)_ __ _ _ ___| |__ __ _| |/ _|
| '_ ` _ \| | '_ \| | | / __| '_ \ / _` | | |_
| | | | | | | | | | |_| \__ \ | | | (_| | | _|
|_| |_| |_|_|_| |_|\__,_|___/_| |_|\__,_|_|_|
VBM: Kpoint 48, band 4 and eigenval -3.683426
CBM: Kpoint 68, band 5 and eigenval -1.141163
Gap: 2.542eV
_____ _ _ ____
| ____| \ | | _ \
| _| | \| | | | |
| |___| |\ | |_| |
|_____|_| \_|____/
As expected, the Gap found is worth 2,542eV [1] .